Dermasector



April 15, 1952 s. G. BERKQW 2,592,533v

DERMASECTOR Filed June 27, 1946 INVENTOR. SHMl/EL. GoRooN skxow HTTORNEY Patented Apr. 15, 1952 UNITED STATES PATENT OFFICE 7 Claims.

(Granted under the act of March 3, 1883, as amended April 30, 1928; 3700.'G. 757) This invention pertains to the art of grafting skin. Theinvention is embodied in a dermasector skin grafting. More specificallyit is concerned with a tape method of skin grafting and a cuttinginstrument therefor.

Devices for cutting skin from the human body have been known (see U.S.Patent No. 2,288,709 to Hood). These earlier devices had handicaps andwere not available for all conditions.

It is an object of the invention to provide a dermasector the depth ofthe cut of which may be regulated with one hand while the other hand isfree to hold the device and which can be regulated from one end of thecutting element; to provide a dermasector that can be rmly held in onehand without danger of slipping; and to provide a dermasector that `canpositively hold taut the tape that is to carry the skin to be grafted.The dermasector of the present invention can cut extremely thin layersof skin without danger of rupture and it does not require foreignmaterial to be applied to the skin to be cut and left upon it, exceptthe tape that is to carry the skin.

Further objects and advantagesv of this invention, as well as itsconstruction, arrangement and operation, will be apparent from thefollowing description and claims in connection with the accompanyingdrawing, in which,

Fig. 1 is a side elevation of a device embodying the invention,

Fig. 2 is a fragmentary cross-sectional elevation, taken along the line2-2 of Fig. 1,

Fig. 3 is a cross-sectional elevation, taken along the line 3 3 of Fig.'1,

Fig. 4 is an end elevation of the device shown in Fig. 1, certain partsthereof being removed, and

Fig. 5 is a schematic ycross-section of a piece of cloth of the typeemployed in the practice of the invention.

The device of the present invention comprises a carrier, generallydesignated lll, that is employed to receive the donor area of skin whileit is being severed from the donor. and to support the skin .inreadiness for it to be applied to the recipient area. The carrier canalso be employed in the operation of applying the donor skin to therecipient area.

The carrier I0 comprises the rigid piece I8 that includes the convexlycurved 'surface 20. The piece i8 is attached to one end of the pedestal24, the attachment being on the side of the piece I8 opposite the curvedsurface 20. The

hand grip 22 is attached to the other end o f 55 the bore.

the pedestal 24, and nger grips 26 are preferably provided attached tothe pedestal along its length displaced a distance away from the handgrip that enables the carrier I0 to be held rmly in the hand of theoperator.

Under preferred practice the described structure of the piece I 8, thepedestal 24 and the hand grip 22 is of solid metal and is madeconsiderably heavy. This enables the grafting operation to be carriedout with steadiness and surety. Other suitable material may be used. Thecarrier lo enables the curved surface 20 to be rolled manually on theskin surface the movement being employed in the operation of severingthe area of donor skin in a manner that will be described more fullyhereinafter.

The area of the curved surface 2B is made large enough to encompasswhatever size of skin area it might become desirable to graft in onepiece, the surface 2U being made somewhat wider to provide an overlap,and somewhat longer to accommodate the carrier cloth that is employed inpracticing the invention in a manner that will be described morefully'hereinafter. In practice the convex surface of the piece I8 isapproximately 1.5" wide and approximately 5.0" long, and thisconstruction has been found satisfactory for practice of the invention.

A cutter 34 is provided, held in position with its cutting edge 35spaced away rom the surface 2U a predetermined distance as illustratedin Fig. 2. The cutter is mounted to swing in a path that is parallelwith the curved surface, the edge 35 being held spaced away from thesurface 20 the precise predetermined distance throughout the swing ofthe cutter 34. This establishes the thickness of the skin that issevered from the donor area and makes it uniform throughout its area. Italso enables several pieces of skin to be cut uniformly to likethicknesses, for example, when an area of skin is to be grafted that ismade up of several pieces positioned edge to edge on the recipient area.

For the described purpose, the curved surface is contoured to describean arc of a cylinder, the central axis of which is preferably positionedin the hand grip 22 to locate it Within the fist of the operator whenhis hand and nngers engage the grips 22 and 26 in the normal manner ofoperating the device. The bore 3|, Fig. 4, is positioned coincident withthe center of curvature of the surface 20, vand the pintle 32 isprovided `to lit the bore 3| and is adapted to rotate in the journalprovided by This construction enables the cutter 34 to be swung in anarcuate path that is parallel to the arcuate surface 20.

Arms I2 and I6 are attached to respective opposite ends of the pintle32, by means of the set screws I5 for example. The cutter 34 is attachedto the cutter support bar I4 by any suitable means such as the screws35. The end trunnion 38 of the bar I4 is projected into the arm I2 atits end opposite the pintle 32, and in a similar manner the other endtrunnion 39 of bar I4 is projected into the arm I6 at its end oppositethe pintle 32. n The bar I4 is thus disposed parallel with the pintle32, the lengths of the arms I2 and I6 between their attachments to thepintle 32 and the bar I4 being equal.

It will be noted that the structure throughout, including the arms I2and I6, the pintle 32 and the bar I4, are preferably constructed ofsolid metal and with considerable weight. Light and flimsy constructionwould detract from precision operation of the device. In practice, thedevice of the present invention operates to cut donor skin inthicknesses of from one to a few thousandths of an inch, and touniformity within limits measurable in fractions of thousandths of aninch. The sturdy construction of the device of the present invention isone of the principal factors that enables such precision operation.

The trunnions 38 and 39 are mounted to rotate in their sockets of therespective arms I2 and I6 for adjustably varying the spacing betweensurface 2U and the edge 35 of the cutter 34.. The trunnion 38 isprovided with the worm wheel 40, Fig. 3, that is driven by the worm 42,the drive being manual by means of the knob 44. Rotation of the knob 44operates to rotate the bar I4 on its axis, and this operates to positionthe edge 35 of the cutter 34 either nearer to or further away from thesurface selectively, depending upon the direction of rotation of theknob 44. See Fig. 2. A conventional set of thickness or feeler gages canbe employed to adjust the spacing of the edge 35 accurately the desiredamount. Under preferred practice the worm and worm wheel 40, 42 aremachined to a tight mesh and without backlash. This enables preciseoperation, and by this means the cutter is held by the worm wheel tomaintain its position of adjustment. The thumb screws 46 are provided asadditional means for holding the cutter in position of adjustment.

At least one of the arms I2 is preferably constructed to form a handgrip as shown. The pintle 32 is made longer than the bore 3I for itslongitudinal reciprocation. Grasping the handle of the arm I2, theoperator is able to reciprocate the cutter 34 longitudinally of itscutting edge 35 to produce slicing action, and meantime he rotates thepintle 32 in the bore 3I whereby a thickness of skin of predeterminedarea is severed from the donor. As part of the same operation, thecarrier II) is actuated with the other hand to roll surface 20 on thedonor skin, which is held against the surface 20 by adhesion. Rollingthe convex surface 20 lifts the donor skin to feed it to the cuttingedge 35, which is positioned manually by handle I2 to be kept locatedwhere the skin is lifted the desired amount.

Under preferred practice, the donor skin is transferred from the donorto the recipient in condition of being adhered to a carrier cloth.Pursuant to this purpose the carrier cloth is attached to the convexsurface 20 in backing engagement therewith during the operation ofsevering the skin from the donor area. Clamps are provided to hold apiece of carrier cloth pressed against the bulge of the convex surface20 in position to receive the donor skin and hold it while it is beingcut from the donor, the carrier cloth also serving to hold the donorskin until it becomes grafted on the recipient.

Each clamp comprises the cleat 28, attached to the piece I8, preferablyon the side thereof opposite the surface 20 where it does not reduce theeffective area of its backing surface 28 and thus diminish the area ofdonor skin that can be transferred from the donor to the recipient withthe device of the present invention. Each cleat 28 comprises theterminal ange 2'I, and a resilient or spring clip 30 is provided foreach cleat 28, the clip 3U being provided with the groove 29 companionto the ange 2'I. The several iianges 2'I and their respective companiongrooves 29 are directed in opposite directions away from each other toprovide tortuous reentrant paths for the cloth that operate to take upslack thereof when the cloth is stretched and clamped onto the piece I8.The end of a strip of cloth is clamped in one of the clamps 28, 30, andis spread smoothly over the surface 20 to position its other end forengagement by the other clamp. When the clip 30 of the second clamp isapplied to its cleat 28 with the fabric between, slack is taken up, andtension is applied to the cloth to stretch it taut over the convexsurface 20 and in .facing engagement therewith. Each clip 38 is providedwith a finger grip 25 to facilitate its attachment to and removal fromits cleat 28.

The cloth for use with the present instrument and method should havesubstantially no stretch, should be adhesive and easily pliable, give noskin irritation or allergic reaction, preferably be transparent andshould have the ability to withstand autoclaving for l5 minutes at 250C. and 15 pounds pressure withous signicant loss of the before-mentionedproperties. Some substances that are pliable to an extent, e. g., paper,are unsuitable because they are not pliable enough. Paper will bend in alittle fold which may give a mis-cut or allow undesirable collection ofsecretions thereunder. The pli ability of a soft cloth is needed and isdenoted herein by easily pliable.

The carrier cloth can be woven or otherwise fabricated in any suitablemanner that resists stretching in the longitudinal and transversedirections, and should be constructed of a yarn that is strong andstretch inhibiting. The cloth should be of uniform thickness, and tothis end yarns of uniform thickness should be employed in thefabrication of the fabric. Accordingly, a strong, stretch-inhibitingyarn of synthetic filament has been found most suitable for the purpose.Instead of the cloth being cut to width, it preferably is provided inthe form of a ribbon or tape, fabricated to a desired width to ft thewidth of the surface 20, such a fabric having non-ravelling edges.

The carrier cloth should be impregnated with an adhesive, or coated withan adhesive on one surface at least that is the exposed surface when thecloth is positioned in facing relationship with the surface 20 of thepiece I8. Under preferred practice the cloth is provided alreadyprepared with an adhesive instead of the adhesive being applied when thecarrier I0 is being readied spaanse 5 for use. Manufacturing controls offabricating the cloth enable uniform thickness `of .adhesive to beattained more easily, and it ispreferred to eliminate rfrom the`operation of making .a skin graft the problem of providing uniformadhesive thickness.

As illustrated in Fig. 5, a suitable structure of ribbon 51 .comprisesthe cloth 48, with a coating 50 kof adhesive, which may be a natural orsynthetic rubber compound. A coating of .004"l has been lfoundsatisfactory for the tape 51, which may have an upper protective sheet52, if desired, and a lower sheet 54 to protect the coating 5U. Thelower sheet 54 is removed before the tape is used.

The operation of the device vand method are as follows: The donor andrecipient skin areas are prepared as usual, washed with alcohol andrinsed with ether. A test piece of the tape is tautly attached to thesurface 20 in the manner hereinbefore described, with its adhesive sideexposed. The skin carrier I is held in one hand engaging the hand Aandfinger grips 22 and 26, while the knob 44 is adjusted with the otherhand to bring the edge 35 of the knife 34 the desired distance from thesurface of the adhesive 50 on the tape 51. This usually is done byvisual inspection but gages of a conventional set of feeler gages can beused if desired. The distance between the adhesive and the knife edgedetermines exactly the depth of the skin that will be cut olf from thedonor skin area. This may be one or two or more thousandths of an inchdepending upon circumstances. This gives a precision heretoforeunattainable and enables the donor skin to be cut very thin. The latteris most important, especially in the case of skin of babies. Thearrangement of the parts of the device with the cutter support bar I4rotatable with the pintle 32 enables one hand to hold the device IIIwith the curved surface 23 disposed upwardly while adjustment of theknife edge 35 ismade quickly and accurately by the other hand operatingfrom one end only of the bar I4.

The test piece of tape may be discarded, and a length of autoclaved tapeis smoothed down over the donor skin and adhered thereto. The width ofthe carrier cloth may be greater than the width of the donor area ofskin, and is preferably approximately 1.5" wide to correspond with thewidth of the curved surface 20. The piece of ribbon 51 is longer thanthe donor area of skin, and is made about 2.0" longer than the curvedsurface 20 to allow for it being engaged at its ends by the clamps 28,30.

The skin carrier I0 is now placed on the tape 5l and one end thereof isfastened in one of the clamps 28, 30. The ribbon of cloth is now spreadover the surface 20, and this places the opposite end thereof inposition for engagement with the remaining clamp 28, 3B. The operationof fastening the second clamp 28, 30 serves to take up slack in theribbon 5l and to apply tension thereto, holding the tape taut againstbulge of surface 20. The surface 20 is then rolled over the surface ofthe donor skin until one end of the donor area of skin by adhering tothe cloth 5l is raised slightly. The other hand of the operator byexerting force on handle I2 swings the knife 34 under surface 20severing the skin from the donor area, and the carrier I0 is rolled onthe donor skin progressively in advance of the cutter 34 imtil thedesired area of skin has been severed. Shaft 32 may be moved axially inthe bore 3l of the hand grip 22 so that the operator can give a back andforth sidewise motion to the handle I2 and knife 34. The side edges ofVknife may be sharpened to cut, if necessary, during the sidewisemotion.

When the entire desired donor larea of skin has been severed, the skincarrier I is free to be lifted away from the donor. The tape may or maynot be left on the device, but the skin is not removed from the tape.The skin is placed in position for the graft and any free end of tapemay be used to secure the skin in its new position. E'Xtra layers oftape may be placed across the originaltape more firmly to secure it andthe skin. When necessary the Vskin and tape are first removed from thecarrier I0 and the skin and transparent tape may be clipped to specialsize and shape as when a plurality of grafts are to be juxtaposed.

The present device and method permits the removal of several squareinches of skin all with a uniform depth which may be no more than oneone-thousandth of an inch. The cloth 48, with the severed area of donorskin adhered thereto, operates to hold the skin area to its originaldimensions and prevents it from shrinking. Prior art practice requiresthat the grafted skin be stretched over the recipient area and stitchedin position on the recipient area by means of sutures. Such sutures areliable to fail,`

and in addition constitute a dangerous source of infection. By means Vofthe cloth 48, the graft is maintained under normal tension at all times.The necessity for sutures is removed. The simplicity of operation,including determination of depth of cut of the present device permitsand enables a relatively unskilled operator to use it in situationswhere speed is paramount.

It is to be understood that various modifications and changes may bemade in this invention without departing from the spirit and scopethereof as set forth in the appended claims.

The invention described herein may be manufactured and used by or forthe Government of the United States of America for governmental purposeswithout the payment of any royalties thereon or therefor.

What is claimed is:

l.. In a dermasector, a rigid piece embodying a surface that describes aconvex arc of a cylinder, a rigid pedestal attached to the piece andprojecting away from it on the side opposite the arcuate surface, thepedestal comprising a hand grip that embodies the axis of the arcuatesurface and includes a bore coaxial therewith, a pintle fitted to bearin the bore and being longer than the bore to be movable longitudinallythereof, a pair of rigid arms respectively attached to correspondingopposite ends of the pintle, a bar adjacent to the convex surface andextending parallel with the axis thereof, each of the arms comprising abearing for the bar, the bearings of the several arms being coaxial andbeing parallel with the axis of the arcuate surface, a cutter supportedby the bar with its cutting edge parallel with the arcuate surface andoff-center of the axis of the bearing, the cutting edge being spacedaway from the arcuate surface a predetermined distance and the bar beingrotatable in the bearings to adjust the space between the cutting edgeand the arcuate surface.

2. In a dermasector as defined in claim l, a worm carried by one of thearms, a worm wheel secured to the bar in mesh with the worm, a

manually rotatable knob secured to the Worm for rotating the bar formaking the adjustment of the space between the cutting edge and thearcuate surface.

3. In a dermasector, a rigid piece embodying an arcuate surface, asupport for the piece embodying the axis of the arcuate surface andincluding a coaxial pintle, a cutter and a bar supporting the cutterdisposed with its cutting edge spaced away from the arcuate surface apredetermined distance, a pair of rigid arms respectively attached tocorresponding opposite ends of the pintle and the bar, each of the armscomprising a bearing for the bar, the bearings of the several arms beingcoaxial with each other and being parallel with the axis of the arcuatesurface, a cutter supported by the bar with its cutting edge parallelwith the arcuate surface and off center of the axis of the bearings,adjusting mechanism to rotate the bar in its bearings to vary thespacing between the cutting edge and the arcuate surface.

4. In a dermasector as dened in claim 3, the adjusting mechanismcomprising a worm gear attached to the bar, a worm in mesh therewith,and a manually rotatable knob operable to rotate the worm.

5. In a dermasector, a rigid arcuate piece comprising a surface thatdescribes a convex arc 'of a cylinder, a rigid support for the pieceprojecting away from the inside thereof and embodying the axis of thearcuate surface, a cutter, a support for the cutter holding its cuttingedge parallel with the arcuate surface and spaced away therefrom apredetermined distance, the support for the cutter comprising a pivotfor swinging the cutter on an axis coincident with the axis of thearcuate surface, an attachment to hold a piece of cloth in tautcondition against the arcuate surface and comprising a pair of clampsrespectively engaging each of opposite ends of the piece of cloth andholding it near the end of the arc of the surface inside the curvethereof, one clamp comprising a cleat attached to and extending awayfrom the arcuate piece inside the curve of the arcuate surface, aterminal ange projecting laterally away from the direction of extensionof the cleat, a spring clip contoured companion to the cleat and itsflange to stretch the cloth opposed to the opposite clamp by the clothbeing gripped between the cleat and the clip.

6. In a dermasector as defined in claim 5, the second clamp comprising acleat and a clip like the first clamp, the second cleat being attachedto the arcuate piece inside the curve of the arcuate surface.

7. In a dermasector, a rigid piece embodying a convex surface thatdescribes an arc of a cylinder, a pedestal rigidly attached to the pieceon the side opposite the arcuate surface at a point opposite the centerthereof, and projecting away from the piece to and beyond the axis ofthe arcuate surface, the pedestal comprising a hand grip around andextending along the axis of the arcuate surface, the handle having abore coaxial with the arcuate surface, a pintle tted to bear in the boreand being longer than the bore to be movable longitudinally thereof, acutter disposed with its cutting edge positioned spaced away from thearcuate surface a predetermined distance, a pair of rigid arms attachedto respective opposite ends of the pintle and each connected with an endof the cutter, a bar adjacent to the convex surface extending parallelwith the axis thereof, each of the arms comprising a bearing for thebar, the bearings of the several arms being coaxial and being parallelwith the axis of the arcuate surface, the bar comprising an attachmentfor the cutter to support it with its cutting edge off-center of thebar, the bar being rotatable in the bearings to adjust the space betweenthe cutting edge and the arcuate surface.

SAMUEL GORDON BERKOW.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 1,993,899 Rieske Mar. 12, 19352,079,979 Worthington May l1, 1937 2,288,709 Hood July 7, 1942 2,442,433Reese June 1, 1948 OTHER REFERENCES Jenny, J. A.: Modification of thePlasma Fixation Method of Skin Grafting by Use of Bobbinet and a MirrorAttachment," Surgery, Gynecology and Obstetrics, June 1945, page 471.

